MYTH

Sharks don't sleep in the traditional sense, but they do have periods of rest and reduced activity.

Source: Do Sharks Sleep? - Discovery Channel

MYTH

Of over 500 shark species, only about 10 are considered dangerous to humans. Most sharks are harmless.

Source: Shark Species and Human Risk - NOAA Fisheries

MYTH

While rare, sharks can and do get cancer. This misconception led to harmful cartilage supplement marketing.

Source: Do Sharks Get Cancer? - Journal of Cancer Research

FACT

Sharks evolved around 400 million years ago, while trees appeared about 350 million years ago.

Source: Shark Evolution Timeline - Smithsonian Ocean

MYTH

While sharks have an excellent sense of smell, they can only detect blood from about a quarter mile away under ideal conditions.

Source: Shark Sensory Biology - Florida Museum